External battery extension for Boom

[philippe_44]

A work of beauty. Too bad I'm electronically impaired... and I would just mess this up. But great idea and execution.

Also, haven't you thought about using high discharge batteries to avoid problems? Stuff like Sony's VTC 4/5 or LG HE4. They are rated for 20+A.

Thanks The Boom power supply is rated 12V/2.5A (from memory) and the battery pack I'm using is classical LiIon 3x18650 cells that has a limiter circuit of 8.5A (they can go higher of course as these cells have extremely low impedance, but you *want* the limiter) and I also have a switch on my design to select either battery or external power supply that as a limiter at 4.5A. This is plenty of current to feed the Boom, the internal power supply has a bank of large capacitors to absorb short peaks

[chill]

Philippe started this thread several years ago, and I discovered it a couple of years after that. Philippe sent me a bare PCB, but sourcing and soldering the surface-mount components was just too much of a task for me. So then he had some fully populated PCBs made and he sent me one to test. Yet again I let him down - he provided a 3D-printable box, but my printer was (still is) in need of fettling and I could never get a good print, so the PCB lay unused for a year or two.

Fast forward a couple of years and I know a bit more about how to get better prints from my 3D printer. I've also had a lot more practice with AutoCAD, which has allowed me to tweak Philippe's original box to make it print better on my printer (rounded corners!), and to incorporate a couple of specific features that suit my own purposes.

So now, finally, I'm up and running with this little marvel. It works beautifully. It sits in the recess at the back of the Boom, and provides a pass-through for the DC supply, which also keeps a 3x18650 cell pack charged, so that when the DC supply is removed the battery pack takes over.

I have a couple of Booms that will benefit from this: The first one lives in the kitchen where I use wired ethernet (the reason for one of the tweaks to Philippe's box design), which I can now take out into the back garden. The second is one that I use in my camper van, where the 12V DC requirement is perfect. I used to use a 12V extension cable, but now I can use it completely without wires.

[ALW]

...I remembered I had one of these (https://www.amazon.co.uk/gp/product/...?ie=UTF8&psc=1).

Sadly no longer available, but essentially a 12Ah battery pack, with built-in 19 / 16 / 12V outputs. I don't use it for it's original purpose anymore, so made a lead to connect it to the Boom. It works superbly, giving pretty much all day use in the garden, even at high volumes. I started playing at around 10am this morning and the battery died just after 5pm.

It's really amazing how fantastic this thing sounds and how loud it can go, with apparent ease, I just need to fix the display, there's not a hope of reading it outside currently!

Andy.

[Man in a van]

all day use in the garden, even at high volumes. I started playing at around 10am this morning and the battery died just after 5pm.

Other ways to annoy your neighbours during lockdown are available.......

ronnie

[philippe_44]

I've given a full upgrade to another one of my Boom (Display, Speakers, Wifi, Coating) so I decided to add my battery extension. I've used the modified casing made by @chill and I have to say that it's a much better fit than mine, it looks much more "integrated" with the rest of the Boom

It's unfortunate that the Boom does not have a "low power" or "off" mode as the battery can only last for a limited amount of time even with dark display, but still, that makes it the best portable audio device IMHO, even after all these years (just after SqueezeAMP-based devices of course )

[ALW]

I've been using my Boom in the garden with a USB battery pack that has a 12V output, unfortunately these (https://www.amazon.co.uk/gp/product/...?ie=UTF8&psc=1) don't seem to be available any more, but there may be an equivalent at a sensible price. This one was only £21 when I bought it.

It's a 12Ah battery, with a selectable 12 / 16 / 19V output and gives around 7.5 hours of continuous use on the Boom, even at quite elevated volumes. It's reminded me just how good the Boom is, compared to a similarly powerful Sony Bluetooth speaker I have, the clarity and musicality of the Boom is streets ahead. Active speaker operation is such a big win.

I've just made a simple lead that connects the two (the one in the image was a lash up, held together with masking tape!), but I may look to make at a 3D-printed holder that attaches to the Boom - I hadn't even realised there were screw fixings under that recess at the back!

I need to fix the display, it's impossible to see in daylight now!

[philippe_44]

I've just made a simple lead that connects the two (the one in the image was a lash up, held together with masking tape!), but I may look to make at a 3D-printed holder that attaches to the Boom - I hadn't even realised there were screw fixings under that recess at the back!
I need to fix the display, it's impossible to see in daylight now!

There is piece that is screwed to the boom using existing mounting holes and then the rest box with battery and charger slides into it.

[chill]

I may look to make at a 3D-printed holder that attaches to the Boom - I hadn't even realised there were screw fixings under that recess at the back!

If my AutoCAD file for the box shown in Philippe's photo would be any use to you as a starting point, drop me a PM.